Precision jig-boring machine



Feb, 12 1924. 1,483,393

B. T. STEBER PRECISION JIG Bom-NG MACHINE Filed qgiy 1.!1921 5 sneets-sheet 1 @gy/W@ Feb. 12 1924. 1,483,393

B. 1'. sTAEBER PRECISION JIG 'BORING MACHINE Filed July l, 1921 V 5 Sheets-Sheet J/ J6' i, s i f? J5 J y .ze 1 @m @mi ,91ml f YJ 31a/ventola ervzaeZ/'ter @ttor new B. T. STEBER PRECISION JIG BORING MACHINE Feb. 12 1924.

lFiled July l, 1921 Sheets-Sheet 5 i (gn/ventole emm'djifel' attozmq Feb. 12 1924. 154835393 B. T. s'faBER PRECISION JIG BORING MACHINE Filed July l. 1921 5 Sheets-Sheet 4 mf A gwuzntoz a. T. sTEBER PRECISION ne BORING incarna Feb. 12 1924.

Filed July 1. 1921 5 Sheets-Sheet 5 Patented Feb. l2, i922@ liitd BERNARD fr. screens, or orrounnwvonn.

PRECISION JIGV-ORING HIACHINE.

Application filed July .1,

To all whom t muy concern.'

Be it known that l, BERNARD T. Srnnnn, a citizen of the United. States, residing at Utica. in the county of Oneida and State'ot New York, have invented Acertain new and useful Improvements in Precision Jig-Boring Machines; and l do hereby .declare the following to be a full, clear, and eXactdescription ot the invention, such as will enable others skilled in the art to which it appertai'ns to make and use the same.

This invention relates to improvements in boring machines, and has as its primary object the relinement. of precision in the tormation and location of apertures or recesses in material both with respect to the proportions of each recess and its relation to others, the unit oit measurement being* that of the micrometer division of one ten-thousandthl of an inch or less. l

With this and other detail objectsvin view as will in part hereinafter become apparent and in part be stated, the invention ycomprises certain novel constructions, combinations and arrangements of parts as subsequently specified and claimed in the accompanying` drawing,-

Figure l is a side elevation of an apparatus embodying the features ot the present invention.

Figure 2 is a front view thereof.

Figure 3 is a fragmentary view in side elevation looking` 'at the opposite side to that seen in Figure l, the driving belt-.being removed..

Figure i is a fragmentary, vertical section taken on the plane indicated by line 4-4 of Figure l, parts bein-g' seen in elevation, and the parts being shown out of clutch.

Figure 5 is a similar view of the clutch portions of the parts seen in Figure 4:, parte` being` broken away and the clutch members being` shown in clutch.

F ionre 6 is a fragmentary face view ot' the clutch hub portion of the worin gear detached.

Figure 7 is afragmentary, .vertical section taken along the main spindle approximately on the plane indicated by line '7 7 ot Figure l, and looking in the vdirection indicated by the arrow but with adjacent parts omitted.

Figure 8 is an enlarged, detail., tragmentary, axial section taken through the leal. semi no. @areas rear idler pulleys and adjacent parts, parts being seen in elevation. y

Figure 9 is aside-'viewfot .the parts seen in Figure .with the friction disc omitted.

tachable tool holder detached.

Figure 14 is a fragmentary plan of the lateral brackets and ydriving gears taken from a plane lying,` parallel to the longitudinal axisI of the friction ygear driven shaft. Y

ln thermaking of `holes in parts Awhich must be constructed withprecision, such, for

instance, as gun-work, sewing machines.'

automobile parts, and interchangeable parts of other apparatusitis customary to clamp the parts to be bored in drill `jigs which contain hardened steel bushings for guiding the drills so that the holes will be identical. It will thus be understood that thejigs used for suchr wor-lt as-this Imust themselves be made with extremeaccuracy. The present invention is designed for the making ot such drill jigs and the assurance ot their exact precision, and it is one vof the objects'of the present invention to provide torthe accurate spacingr and boring of the holes in the drill iig. @ne method now commonly practised by tool makers involves the employment of a master plate and square wherein size blocks of yguaranteed accuracy are spaced.

between the work and the parts of the square corresponding to the requireddistance apart for tliehojles.` :In this method, the master plate, square and .size blocks are clamped to the face plate ot an ordinary lathe, and the combinations of the-blocks are varied for adjusting fthenvvork each time a new hole is to be bored` and this-iscontinued until all of the holes are correctly: bored. There are obvious ditliculties in this method arising from the tact that the lathe spindle is horizontal and the face plate is vertical, which leads to diliiculty in keeping the little size blocks in place while being adjusted. Beside the loss of time thus represented. the lathe, it used for other purposes, is liable to get out of true,77 and further difficultyv arises when the work happens to be longer than can be accommodated in a small lathe, which condition would necessitate the employment of a clumsy lathel with a large tace plate. Some times, for these reasons, a milling machine is used whereon the plate, upon which the work is to be clamped, lies in a horizontal plane, but the milling machine plate is mounted on a movable slide which.l in turn, is mounted on other slidable parts` and it is found in practice that eXtreme accuracy is difficult if not impossible to attain with so many moving parts where the bearings must have a little play in order to move freely, but which play will record ditferently at different times. It will be understood, of course, that when the work is clamped to a lathe.l the work revolves withthe face plate while clamped to a milling machine bed the boling tool revolves and the work stands sti On the present improved machine, the work is clamped on a stationary plate and the boring tool is revolved. v

Referring to the drawings by numerals, 1 indicates the working table or bed plate which is supported on any appropriate stand, parts of which are broken away in the drawings for saving of space. As best seen in Figure 12, the plate 1 is formedwith a number of threaded apertures 2 `for receiving the clamping bolts 4 of clamps 5. Each clamp 5 is formed with a slot 6 for accommodating its respective bolt 4 and allowing adjustment of the clamp, the clamping action being completed through the operation ot a tension screw 3 provided for each cla-mp 5 and arranged with its head in position for engaging the face ot plate 1. The square 7 and appropriate size blocks 8, ,8 are employed for locating the plate 9. which is the part being operated upon. When the plate to be operated upon is too large to allow the employment of the square 7, a substitute for such square is provided in the application of edge plates 9, 9 clamped by .bolts 10 to the edges of the table or tace plate 1. Each plate 9 is preferably slotted at 11 tor each bolt 10, so that the respective plates 9 may be adjusted longitudinally as required. and the edges of the plate 1 are formed with spaced threaded apertures 12 for lgreater adjustments of the plates 9 than permitted by the slots 11. there being enough of the apertures 12 spaced about the several edges of plate. 1 to allow plates 9 to be located as well as adjusted as required, according to the work to be operated upon.

Mounted on the table 1 the stinnlard 13 of the main l'raine 14 ot the machine. Upstanding from the main 'trame 14 is a supplemental frame 15 which is bifurcated at its upper portion and provided with jonrnal bearings in which is journaled the shatt `16 carryingl the usual cone pulley 1T and projectingl rearwardly beyond the rear arm ot the supplemental Lt'rame 15. Fixed to such rear portion of shalt 1G is a driving pulley 18 over which is passed a belt 19, which extends downwardljf and is laced about idler pulleys 2() and 21 (best seen in Figures 2 and 8) and passing thence about a pulley 22 keyed to the main spindle 23 hereinafter described. or otherwise fixed thereto in any suitable manner. The employemeut or' the pulleys 2O and 2l enables the endless belt 19 to have both ot its laps turned ironi a vertical to a horizontal path. of travel, so as to receive power from the verticallydisposed pulley 18 and deliver power to the horizontally-disposed pulley 22.

As best seen in Figure 8, the pulleys 2li and 21 are mounted on a shaft 24 extending through and fixed in the .traine 14. Lubrieating ports 25 are preferably formed in the, shaft 24 for supplying lubricant to the pul- -leys 2O and 21, and pulley 2() is retained on the shaft 24 by a collar 26v adj ustablgy fixed to the shaft 24 by a set screw 27. Pulley 21 is retained against axial separation from shaft 24 by a head 28 on the shaft spaced slightly from the adjacent parts ot the; pulley 21 to allow of axial adjustment 'thereof. The pulleys 20 and 21 are flanged tor guiding belt 19, and the outer flange ot pulley 21 is enlarged to torni a friction disc 29 designed to engage and actuate a Friction gear 3() fixed to a shaft 31 extending); across the extended axis of the sli-att 24. Shaft 31 is slidingly mounted in a sleeve bracket 32 extending laterally troni the rear portion ot traine 14 and in a pair ot spaced or similar brackets 9)?) and B4 extending laterally trom an intermediate portion olz traine 14. Keyed to the shaft 21 between the brackets 33 and is a pinion 35 arranged to be revolved by the sha'lt while leaving` the shaft 'tree to slide longitudinalljVv through its several supporting` sleeve.

brackets and through the pinion. The shatt 31 is arranged in an inrlined plane. and at its lower forward end is provided with an operating` handle 36 adapted to be grasped by the operator for shitting` the sha-tt tor moving the gear 3() across the tace ol: the friction disc 29. The shaft 31 is 'termed 7ith a series of annular grooves BT. and "a spring-pressed pin 3S is carried by the sleeve 34 in position tor normally engaging one ot the grooves 37 for retaining the sl itt 3l in any'given adjusted position. To vary the location of the gear with respect to the friction disc 29. it is opl-v necessary to pull out the pin 539. grasp the handle shift the shaft 3l to the deeircdposition, and allow the pin 38 to drop back into the newly-positioned ,'roove 37. Thus the gear may bc moved from the rapidly driven position near the periphery of disc 2), a' seen in Figure 1. .inward relative to the disc 29 for decreasing the speed until it reaches the axis of the disc it will be noted that the disc 29 is formed with a depression or recess 39 about its axis in which the periphery of the gear 30 may lie out of contact with the disc and allow the gear to remain stationary while the disc 29 revolves. Further movement of the gear 30 carrying it beyond the axis willJ bring it into contact with the surface of the friction disc 29 in position. for receiving reverse motion, and the speed of such motion may be increased from the minimum adjacent the depression 39 to the maximum at the periphery of the disc 29. To enabley adjustment of the gear 30 on its shaft 31, the gear is provided with a boss 40 having a set screw 41 for locking the gear 30 to the shaft 31.

In order to take up wear between gear 30 and friction disc 25hr provision is made for the adjustment of the disc 29 along its shaft 24 toward gear 30, this being preferably accomplished by the employment of a series of pins engaging the pulley 21 and adjustable axially with respect thereto. There may be any desired number of pins 42, a minimum of three being preferably used, as seen in Figure t), one end of each pinresting against a washer 43 let into the face of the pulley 21. The opposite end portion of each pin 42 from that engaging the washer 43 is preferably enlarged and threaded to form a screw portion 44, which is threaded into an appropriately-arranged threaded aperture 45 in the frame 14. Each yscrew portion 44 has its outer end formed with. a kerf to receive a screw-driver, the pulley 2O being formed with apertures 46 adapted to register with the apcrtru'es 45 and of a size to admit the introduction of a screw-driver to the kerf of the respective screw portion 44, whereby the pins 42 may vbe adjusted for moving the friction disc 29 toward the gear 30.

Journaled in the brackets 33 and 34 between the pinion 35 and the main frame 14 is a shaft 47 carrying a gear wheel 48 meshing with the pinion rThe forward portion of shaft 47 extends beyond its bearing` in the bracket 34 and is formed with a worm 49 which meshes with a worm gear 50. The worm gear 50, as best seen in Figures 4 and 5, is journaled on a transverse shaft 51, which shaft is., in turm jcurnaled in brackets 52 outstanding forwardly from the frame 14. Slidingly and rotatably mounted on the shaft o1, outside of the face of and spaced from the worm gear 50, is a clutch member 53 having clutch teeth directed axially toward the gear 50, and the gear 50, in turn, is formed with a hub 4provided with clutch teeth 54 directed toward and adapted to intermesh with the clutch teeth of clutch member lnterposed between these two clutch members is a clutch collar 557 consisting` of a ring or annulus keyed at 56 (as seen in Figure 4) to the shaft 51 and having a series of radial notches corresponding and proportioned in size to the clutch teeth of clutch member 53, leaving a corresponding series of radial outstanding projections 57 corresponding substantially to the space between the teeth of the clutch member 53, whereby the said teeth may pass between the pro jections 57, when permitted to do so, and interlock with the teeth 54 of the hub clutch member of gear 50. A spring 58 is employed about the shaft 51 outside of the clutch member 53, and is held in tension by the nut 59 threaded onto the end portion of shaft 51 for stressing the clutch member 53 toward a clutching yposition with the clutch member of the gear 50. A Asleeve or. housing 6() preferably encloses the spring 58 and extends from the nut 59 to the clutch member 53 when the clutch member is in its open or uny' clutched position. Housing 60ithus limits theoutward movement of the clutch when opened by hand. A secondnut 61 is threaded onto shaft 51 into engagement with nut 59 for binding the parts and preventing accidental displacement thereof.

A. series of axially shiftable pins 62 is arranged in the hub portion of the gear 50 to slide longitudinally with respect to the shaft 51, each pin y62 being located in the line of the opening between the teeth 54, as clearly seen in Figure 6, so as to contact with the ends of the teeth of the clutch member 53. A collar 63 surrounds and is slidingly keyed to the shaft 51 adjacent the inner face of the t,ear wheel 50, and is provided at one point with a laterally extending cam 64 adapted to co-operate with a corresponding stationary cam 65 extending from the bracket 52. The outer face of the collar 63 engages the inner ends of the pins 62. so that when the collar 63 is revolved with the shaft 51 until the cams 64 and 65 come in Contact, yfurther movemeut, causing the collar 63 to slide axially under the camming actioinavill cause the pins 62 to be moved longitudinally and to correspondingly shift the clutch member against the pressure of spring 58, and continued movement of this character will finally brina' the collar 63 to the position shown in Figure 4 whereat the pins 62 have reached the point where the clutch teeth of clutch member 53 are outside the line of the teeth 54 and in line with the inner face of the ring and its projections 57, so that revolution of the gear may continue without causingfurther movement of the shaft 5l. the ends of the pins riding across the inner faces of the teeth of clutch member and across the inner faces of the projections 57.

To enable manual control of the clutch just described, the clutch member 53 is formed with an annular groove G6 engaged b y pins 67 of the usual type carried by collar G8 forming part of a hand-operated lever 69. projecting toward the front of the machine in position to be engaged by the operator and pivcted at its rear end, as indicated at 70. to the bracket 34. n

The shaft 5l carries the rackeengaging pinion 7 .lY in position for meshing with the teeth of the vertical racl; 72 slidingly mounted in the forward part of the frame 14. The end portion of shaft 5l, opposite that carrying the clutch parts just described, projects beyond the side of the frame rand is provided with a hand wheel 73 for starting operations and for controlling and varying conditions manually when required.

Pulley 22 is splined to the main spindle 23, so that the latter may move longitudinally while receiving power from the pulley. the said spindle being slidingly and rotatably mounted in bearings 74, 74, carried by brackets 75 outstanding forwardly from the frame 14, the bearings being each held in place by clamping nuts 76, 76. Fixed to the upper end of the rack 72 is an outstanding bracket 77 terminating at its outer end in a ring 78 formed in its upper and lower faces with raceways for ball or similar bearings 79, 79. The ring 78 surrounds the upper end of the main spindle 23 and is connected thereto through the balls 7 9 retained by upper and lower raceway rings SO, 80. Fired to the main spindle 23 so as to leave the main spindle free to rotate while being shiftedk longitudinally by the action of the rack 72.

lfithin the spindle 23 is arranged the collet bar 8l whose upper end is engaged by a hand wheel 82. and whose lower end is bored and tapped to form a threaded opening 83 for receiving the collet 84. Obviously, a number of collets of different sizes may be provided for application tothe bar 31, according to the character of boring instrument to be engaged. The manner of engagement of the shank of the boring` instrument by the collet bar is well understood in the a rt. consisting in the gripping action of the lower ond portion of the collet 34 incident to the drawing; of the head of the collet into the spindle 23 by the "-:iotation of the collet bar 8l through manual manipulation of the wheel 82. `Release of the tool is acomplished by the reverse action. and it will be understood, of course, that a dfill, or the shank of any desired chuck, may be employed as well as any other form of boring` instrument.

ln operation, the pulley 17 being` driven from a source of power not illustrated, and the spindle being in its uppermost position. the cams 64 and 65 (see Figure 4l will be in engagement so that, although the spindle 23 will be revolving and the parts 29. 30. 3l, 35. 48, 49 and 5() will be revolving, the other parts will be stationary. rlhe operator grasps the handle of wheel 73 and turns it slightly, thus moving the cam 64 ottl of the high point of cam and allowing the teeth of clutch member 53 to start to enter thespaces between the teeth of the clutch member carried by gear 50. This movement allows power to be transmitted from gear 50 through the teeth of clutch member 53 to the radial. projections 57 of the clutch ring` 55, and thence to the shaft 5l. .Rotation of the shaft 5l causes the pinion 7l, meshing with rack 72, to feed the rack 72 downward while the spindle 23 and the boring` or drillingtool carried 'thereby is revolved. Vhen the spindle 23 is approaching its lowermost position, the inclined faces of cams 64 and 65 will come in contact and by the time the spindle 23 has reached the lowermost limit of its movement, the pins 62 will have been moved, by the action of the cams 64 and ('35 and the resulting movement of collar 63, from the position shown in Figure 5 to the position shown in Figure 4, whereat the teeth of the clutch member 53 are out of contact with the hub cluth member of gear 50 and the said gear 50 is thereby permitted to revolve freely on the shaft 5l. It will be noted that the thrust of the cams 64 and 65 is just suicient to cause the parts to take the position seen in Figure 4 for leaving` the gear 50 idle on shaft 51. and when the pins 62 are in the position seen in Figure 4 the ends of said pins will ride across the ends of the teeth of clutch member 53, but will notl be permitted to drop between any two of said teeth because of the presence of the projections 57 of clutch ring' 55, over which projections said ends rof the pins 62 will also ride. Because of the inclination of the sides of the clutch teeth of clutch members 53 and 54, the width of each projection 57 is not quite as great as the distance between adjacent sides of adj acent teeth of clutch member 53 at the free extremity thereof, but the space between said free ends and the respective projection 57 is not as great as the diameter of any of thc pins G2, so that said pins will continue to ride as stated as loira` as the parts remain in the position seen in Figure lt should be observed, of course, that when the parts are in this position, the face of each projection 57 which is presented toward pins 63 is flush with the faces of the free ends of the teeth of clutch member 53. AReturn movement of the spindle 23 to its raised position is accomplished by a similar movement ot the wheel 73 after the shitting of gear 30 across the face of friction disc 29 to the reverse position. It isnoted that the parts come to a stop automatically at the conclusion ot each longitudinal shitt of the main spindleA A plate is located between the table 1 and the lower end ot kstandard 13 torthe purpose of accurately positioning the superimposed framework. It from any cause the exact angularity ot spindle 23 is altered or its exact relative location is varied so that it gets out ot' line or out ot true with respect to the table 1, the plate 85 is removed and shaped to take up the variation, and again introduced so that exact accuracy is assured.

In the use ot the machine, it becomes desirable, in locating the first hole ot the or die, to carry at the lower end ot the spindle a plug of some fixed diameter from which to measure, and to provide a cutting tool positioned to operate upon the plug thus located, in order to malte it absolutely accurate and true. To this end, I have designed the cutting tool holder seen in Figure 13, wherein the holder is shown as consisting ot' an angle block 9() whose horizontal web isadapted to be gripped by a clamp, such as clamp 5, and whose vertical web is grooved to receive the cutting tool 91 in position to be projected longitudinally more or less as required by the adjustment ot a set screw 92 threaded through a part of the wall of the block into position for contacting with the rear end ot' the tool 91. A detachable plate 93. retains the tool 91 against lateral separation from bloc-k 90. The cutter-bar carrying-block is held at any desired point on the plate 1 by means ot one of the clamps 5.

What is claimed iszl. In an apparatus of the class described, the combination, with a trame and a spindle carried thereby, means for shifting the spindle, and means tor rotating the spindle, of a driven belt for actuating the rotating means, an idler pulley for guiding the belt, said pulley having a tace exposed away from the trame, means receiving power from the exposed face of the idler pulley tor shifting the spindle, and means for adjusting the idler pulley axially away from the frame for varying its delivery ot power.

2. In an apparatus ot the class described, the combination, with a frame and a spindle carried thereby, means for shifting the spindle, and means for rotating the spindle, of a driven belt toi' actuating the rotating means, an idler pulley for guiding the belt,

said pulley having a face exposed away` from the frame, means receiving power from the exposed `face of the idler pulley tor shifting the spindle, and pins extending through the trame for adjusting the idler pulley axially away trom the trame for varyingl its delivery of power.

3. In. an apparatus of the class, described. the combination, with a trame and a spindle, means for shitting the spindle relative to the trame, and means t'or rotating the spindle, ol a driven belt for actuating the rotating means. an idler pulley at one side of the trame tor guiding the belt, means receiving power from the idler pulley tor shifting the spindle, and adjustable pins extending` through the trame and en gaging the idler pulley and adapted to adjust t-he same for lvarying its delivery ot power.

e. In an apparatus oi the class described, the combination, with a trame, a spindle rotatably and sliittably mounted therein, means 'for rotating` the spindle, and means tor shitting the spindle, ot a belt foijact-uating the rotating means. a shaft extending through the trame, idler pulleys on the shaft engaging the laps otl the .belt for directing the belt, means carried by` one or the idler pulleys for delivering power for actuating the shitting means,y and means aecessible through the other idler pulley tor adjusting the iii-st idler pulley Vfor varying the delivery of power.

5. Inan apparatus ot the class described, the combination, with a trame, a spindle rotatably and shiictably mounted therein, means for rotating the spindle, and means for shifting the spindle, of a worm, gear for actuating the shitting means, a worm mesh` ing with said gear,y agear Jfor rotating the worm,a pinion meshing with the last-named gear, a shaft shiftable through and splined to said inion, a friction gear carried by said shalit, a friction disc engaging said friction gear, the said shaft being formed with a series of annular grooves, and a spring-pressed pin disposed to successively engage said grooves for retaining the shattin any of various adjusted positions.

t'. In an apparatus of the class described, the combination, with a frame, and a spindle rotatably and shiftably mounted therein, of means for rotating the spindle, means Jfor shitting the spindle, a shaft for actuating the shitting means, a gear freely rotatably mounted on the shaft, means tor rotating the gear, a clutch member engaging the gear, a co-operating clutch member rotatable on the shaft, andan interposed clutch ring keyed to the shaft and having radial projections adapted to extend between the teeth of one of the clutch members.

7. In an apparatus ot the class described, the combination, with a trame, and a spindle rotatably and shiftably mounted therein, of means for rotating the spindle, means for shifting the spindle, a shaft for actuating the shitting means, a gear freely rotatably mounted on the shaft, means for rotating the gear, a clinch member engaging the gear, a co-operating clutch member rotatable on the shaft, an interposed clutch ring keyed to the shaft and having radial projections adapted to extend between the teeth of one of the clutch members, and pins passing through one of the clutch members in line with the teeth of the other clutch member and adapted to be moved for moving the clutch members ont of clutch.

8. In an apparatus of the class described, the combination, with a frame, and a spindle rotatably and shiftably mounted therein, of means for rotating the spindle, means for shifting the spindle, a shaft for actuating the shifting means, a gear freely rotatably mounted on the shaft, means for rotating the gear, a clutch member engaging the gear, a co-operating clutch member rotatable on the shaft, an interposed clutch ring keyed to the shaft and having radial projections adapted to extend between the teeth of one of the clutch members, and pins passing through the clutch member of the gear in' line With the teeth of the other clutch mem ber and adapted to be moved for moving the clutch members out of clutch.

9. 1n an apparatus of the class described, the combination, with a frame, and a spindle rotatably and shiftably mounted therein, of means for rotating the spindle, means for shifting the spindle, a shaft for actuating ythe shifting means, a gear freely rotatably mounted on the shaft, means for rotating the gear, a clutch member engaging the gear, a co-operating clutch member rotatable on the shaft, an interposed clutch ring keyed to the shaft and having radial projections adapted to extend between the teeth of one of the clutch members, pins passing through one of the clutch members in line with the teeth of the other Clutch member and adapted to be moved for moving the clutch members ont of clutch, a collar keyed to the shaft, and a cam for shifting the collar in contact with the pins for moving them to the unclutched condition.

l0. In an apparatus of the class described, the combination, with a frame, and a spindle rotatably and shiftably mounted therein, of means for rotating the spindle, means for shifting the spindle, a shaft for actuating the shifting means, a gear freely rotatably mounted on the shaft, means for rotating the gear, a clutch member engaging the gear, a cti-operating clutch men'lber rotatable on the shaft, an interposed clutch ring keyed to the shaft, and having radial projections adapted to extend between the teeth of one of the clutch members, pins passing through one of the clutch members in line With the teeth of the other clutch member and adapted to be moved for moving the clutch men'ibers out of clutch, a collar keyed to the shaft, a cam for shifting the collar in contact with the pins for moving them to the unclutched condition, and manual means for releasing the contact of the cam.

ln testimony whereof l ali'iX my signature in presence of two Witnesses BERNARD T. STEBER.

Witnesses HOWARD STEBER, MARION STEBER. 

